Page:CAB Accident Report, United Air Lines Flight 823.pdf/30



We believe that the proposed AD contains adequate instruction for eliminating the noted discrepancies. If the overhaul, inspection, and tests provisions contained therein are carried out, the leakage of CO2 into the cockpit from the underfloor cargo compartment fire extinguishing system will be a minimum consistent with approved flight crew emergency procedures for fire protection. These procedures were listed, in part, in our letter of December 15, 1964. Subsequent to compliance with the noted proposed AD, manual discharge of the CO2 system will not be necessary, although this mode of operation will still be available if desired.

All communications received on or before July 27, 1965, will be considered by the Administrator before taking action upon the proposed rule. Since few operators use the affected airplanes, we do not anticipate many comments. In any event, we feel assured that our corrective action will eliminate the problems uncovered during your investigation, as stated in your subject letter.